CarlBrannen
Veteran
I like my cubes to feel solid so I use glue on the internal parts of each cubie. The glue I use is a solvent glue. These glues work by softening the plastic which allows the two sides to be pressed together.
In this video I glue two pieces of styrene (0.1" square) together, end to end:
https://www.youtube.com/watch?v=979eXts6DwM
I let it dry for a while and was unsatisfied with how straight it was so I broke it again and glued it again, this time straighter. Then I tested it for strength here:
https://www.youtube.com/watch?v=yBlq9S8jIYw
I've had some success with superglue, but I've found that superglue can fail suddenly while solvent glues are nearly as strong as virgin plastic. This is called "poor peel strength".
Recently there have been some puzzles where the corner pieces are particularly fragile. The fragility is due to the corner pieces being molded out of three separate pieces. On these puzzles, I suggest gluing the three pieces together. This makes it less likely that one of the three will fail. But if one does fail, you can be sure that the other two will also likely fail. In this event, disassemble the cube, take the broken pieces and distribute them so that no single corner has more than one broken piece. This has been described here on speedsolving.com. Finally, glue all three pieces together with solvent glue and you will have corner pieces that are much stronger than they were before gluing.
Another solvent glue I use is Plast-I-Weld Flex-I-File. You can buy these at stores that sell stuff for plastic model builders. A commercial variety is Weld-On 2007:
http://www.sdplastics.com/ips/bulletin/Assembly_PB2007.pdf
Some other solvent glues suitable for PVC:
http://www.eplastics.com/Plastic/PVC-Vinyl-Glue/WELD-ON-PLASTIC-ADHESIVE-GLUE-IPS-2007-GALLON
There's a popular Weld-On solvent cement that is used to glue PVC pipe together. I have little doubt that this would work well for cube type puzzles but I've never tried it as the solvent glues give a nicer joint. The usual Weld-On primer is blue (to show inspectors that joints are up to code) but it can be obtained in other colors and clear. The glue is familiar to most do it yourself folk:
http://www.weldon.com/solvent/pvc/regular
In this video I glue two pieces of styrene (0.1" square) together, end to end:
https://www.youtube.com/watch?v=979eXts6DwM
I let it dry for a while and was unsatisfied with how straight it was so I broke it again and glued it again, this time straighter. Then I tested it for strength here:
https://www.youtube.com/watch?v=yBlq9S8jIYw
I've had some success with superglue, but I've found that superglue can fail suddenly while solvent glues are nearly as strong as virgin plastic. This is called "poor peel strength".
Recently there have been some puzzles where the corner pieces are particularly fragile. The fragility is due to the corner pieces being molded out of three separate pieces. On these puzzles, I suggest gluing the three pieces together. This makes it less likely that one of the three will fail. But if one does fail, you can be sure that the other two will also likely fail. In this event, disassemble the cube, take the broken pieces and distribute them so that no single corner has more than one broken piece. This has been described here on speedsolving.com. Finally, glue all three pieces together with solvent glue and you will have corner pieces that are much stronger than they were before gluing.
Another solvent glue I use is Plast-I-Weld Flex-I-File. You can buy these at stores that sell stuff for plastic model builders. A commercial variety is Weld-On 2007:
http://www.sdplastics.com/ips/bulletin/Assembly_PB2007.pdf
Some other solvent glues suitable for PVC:
http://www.eplastics.com/Plastic/PVC-Vinyl-Glue/WELD-ON-PLASTIC-ADHESIVE-GLUE-IPS-2007-GALLON
There's a popular Weld-On solvent cement that is used to glue PVC pipe together. I have little doubt that this would work well for cube type puzzles but I've never tried it as the solvent glues give a nicer joint. The usual Weld-On primer is blue (to show inspectors that joints are up to code) but it can be obtained in other colors and clear. The glue is familiar to most do it yourself folk:
http://www.weldon.com/solvent/pvc/regular
